Method and control system for a fifth wheel coupling sliding device having detection of the bent position of towing vehicles and trailers

ABSTRACT

A method and a system for controlling a sliding device for a fifth wheel coupling arranged on a towing vehicle, wherein the sliding device includes a substructure having at least one guide rail oriented in the driving direction, a movable slide, which supports the fifth wheel coupling and engages on the guide rail, and a control unit, to which a motorized drive unit for moving and an actuator for fixing the slide are connected. The invention was based on the problem of providing a method or a control system that minimizes the risk of the trailer bumping into the cab of the towing vehicle, in particular during an evasion maneuver. The problem is solved, among other things, in that a measurement is performed to detect the bent position of the towing vehicle and the trailer, the signal of the measurement is processed in the control unit, and a start-up of the motorized drive unit and/or of the actuator is initiated using said signal.

FIELD OF THE INVENTION

The invention relates to a method for control of a sliding device for a fifth wheel coupling arranged on a towing vehicle, comprising the steps of: the sliding device comprises a substructure having at least one guide rail oriented in a driving direction, a movable slide, which supports the fifth wheel coupling and engages on the guide rail, and a control unit, to which a motorized drive unit for moving the slide and an actuator for fixing the slide relative to the guide rail are connected, performing a measurement to detect a bent position of towing vehicle and trailer, processing a signal of the measurement into a control signal in the control unit, and initiating a start-up of one or more of the motorized drive unit and the actuator therewith. Furthermore, a control system for a sliding device that is especially suited to implementing the method of the invention is placed under protection.

BACKGROUND OF THE INVENTION

Such a sliding device is known, for example, from DE 10 2005 060 124 A1. With the help of a motorized drive unit, a slide with the fifth wheel coupling located thereon can be moved in the lengthwise axis of the vehicle on two parallel disposed guide rails and locked in a predetermined position. When driving fast on the expressway with few curves, the fifth wheel coupling should be moved as close as possible to the driver's cabin, in order to keep the gap between the driver's cabin and the front of the trailer as small as possible and minimize turbulence in this area. According to the known publication, the control unit of the sliding device is connected to the vehicle's control unit so that information as to the vehicle's speed can be called up and the gap between towing vehicle and trailer can thus be adjusted in controlled operation. However, this leads to the problem that the trailer, drawn up as close as possible to the driver's cabin, cannot easily swing past the driver's cabin when negotiating a tight curve, and the corners of the trailer will strike the driver's cabin. This problem also exists with a panic braking, that is, a sudden full braking without avoidance maneuver, which is recognized by evaluation of a braking signal going into the control unit and triggering an extremely rapid backward movement of the slide to increase the gap size.

Another prior art is disclosed by DE 10 2004 045 662 A1 with a sliding device, whose slide position is detected by a position sensor. The signal of the position sensor is provided to a control mechanism. When the gap is too narrow between driver's cabin and front of the trailer, it can also activate the drive unit of the sliding device and thereby move the slide backward.

In practice, however, it has been found that the detecting of the braking signal and the vehicle's speed are in any case suited to recognizing a panic braking without subsequent avoidance maneuver. Here, even when the fifth wheel coupling has been drawn forward, the remaining gap between towing vehicle and trailer is generally sufficient. A simultaneous avoidance maneuver, often leading to a striking of one corner of the trailer against the driver's cabin of the towing vehicle, cannot be detected with the known device. The determining of the position of the slide is not very precise, especially during heavy load-shifting reactions of the trailer, but also in the case when operating equipment is located at the front end of the trailer, so that there is an additional uncertainty as to whether the trailer can swing past the rear of the towing vehicle without collision.

For this reason, the problem of the invention was to provide a method and a control system that minimizes the risk of a collision of the trailer with the driver's cabin of the towing vehicle.

SUMMARY OF THE INVENTION

The problem is solved according to the invention with a method in which a measurement is performed to detect the bent position of towing vehicle and trailer, the signal of the measurement is processed into a control signal in the control unit, and a start-up of the motorized drive unit and/or the actuator is initiated therewith.

By bent position is meant an angled position of the towing vehicle and the trailer in relation to the vehicle's lengthwise axis. In the frequently used sliding devices, the slide is moved on two parallel guide rails by means of a motorized drive unit, such as a hydraulic cylinder, and after reaching the intended position it is secured at both sides to the guide rails. For this, an actuator such as a pneumatically or hydraulically operated cylinder usually moves locking pieces in the direction of the guide rails and is brought into form-fitting engagement with them. This locking of the slide to the guide rails takes strain off the motorized drive unit, especially during heavy braking or collisions.

Instead of a form-fitting locking, it is also possible to dimension the motorized drive unit with sufficient size and do without additional form-fit locking elements. In this embodiment, by actuator is meant a blocking valve, which entraps the fluid located in the interior of the cylinder.

During fast travel on the expressway, the trailer is brought up close to the driver's cabin of the towing vehicle by the sliding device, in order to keep the gap width between driver's cabin and front of the trailer as narrow as possible. This minimizes turbulence and, thus, also the fuel consumption. In event of a sudden avoidance maneuver, the fixation of the slide is released and the slide is pushed back on the guide rails. With the help of the method of the invention, the spatial position of the trailer is directly monitored, so that when parts of the trailer come close a moving of the slide to a rear position is initiated.

Preferably, an angle gradient or in the case of a distance measurement a distance gradient is generated from the signal of the measurement in the control unit, or this is relayed to the control unit. The terms angle gradient and distance gradient are used synonymously and merely underscore the possibilities of different measurement values detected. The angle or distance gradient shows the steering wheel movement during driving or a change in the measured value furnished by the sensor per unit of time, in order to adjust the size of the gap in this way. With this procedure, there is no need to quantitatively infer the magnitude of the current bend angle and use it to determine the position of the fifth wheel coupling on the guide rails. With this procedure, it is possible to determine in advance whether the steering movement performed by the driver is due to negotiating a long curve in normal driving operation or a sudden avoidance maneuver. Thus, in particular, a quick adjustment is accomplished in an emergency, i.e., in the case of a fast avoidance maneuver.

It has been found to be especially advantageous to additionally generate a braking gradient from the braking signal of the vehicle's brake system in the control unit or relay such to the control unit. The braking gradient serves to indicate whether a strong or weak application of the brakes was done by the driver. One can use as the parameter for this, e.g., the brake pressure or the pedal movement per unit of time. In particular, the available pedal movement of the vehicle's brakes can be detected by two sensors, situated at the beginning and end of the pedal movement. During a sudden panic braking, the driver will step quickly on the brake pedal to avoid an impending accident. This results in a fast pedal movement and a correspondingly high braking gradient.

The slide can be locked by the actuator upon exceeding a predetermined braking gradient and dropping below a predetermined angle gradient. This scenario corresponds to the driving situation of a full application of the brakes with no significant movement of the steering wheel. Even if the trailer draws near to the driver's cabin due to shifting-load reactions, no collision is expected. For this reason, the actuator remains in the locked position, while in the case of a form-fitting engagement an additional safety is achieved, since the slide is not held solely by the motorized drive unit. The involvement of the aforementioned parameter can be used advantageously to move the relevant safety systems into a readiness mode. Thus, for example, the hydraulic pump of the motorized drive unit can run up to speed, in order to provide a sufficiently high operating pressure as a precaution.

Advantageously, the locked position of the slide is released by the actuator upon exceeding a predetermined braking gradient and exceeding the predetermined angle gradient. In this scenario, there is a sudden steering maneuver of the driver in addition to a full braking, since it is sometimes necessary to avoid an obstacle. To avoid a collision of the front of the trailer with the driver's cabin of the towing vehicle, the slide must be brought into a rear position on the guide rails and thereby increase the gap width between front of trailer and driver's cabin. For this, it is necessary to release the locked position of the slide.

Advisedly, the actual speed of the towing vehicle is also provided to the control unit and below a predetermined minimum speed the slide is held in a rear position on the guide rail or rails. This procedure prevents a continual movement of the slide at low driving speeds or during shunt operation. Any way, the air resistance is hardly a factor here. Furthermore, when parked or in shunt operation this prevents an unintentional backward movement of the trailer and, thus, damage to vehicles, buildings, or other objects located behind the trailer.

The invention is likewise implemented for a control system, in which the control unit is connected to at least one sensor, which provides a measured value for detecting the bent position of towing vehicle and trailer, and it interacts with the drive unit and/or the actuator.

According to a first advantageous embodiment, the sensor is disposed in the area of the steering system and it detects the steering wheel angle of the towing vehicle. From the steering wheel angle of the towing vehicle, one can indirectly infer the bent position. This arrangement is especially preferred, since a signal from the sensor is available to the system very early in time, i.e., immediately after the steering motion. In this case the sensor can interact in particular with the steering wheel and/or the steering linkage and/or the steering gear.

In a second preferred embodiment of the invention, the sensor detects the relative angle between towing vehicle and trailer. A sensor suitable for this can be, for example, a rotary encoder. The rotary encoder should be disposed, for example, on or in the fifth wheel coupling. In this case, a rotor can bear against the underside of the trailer plate and detect a sideways movement of the trailer. It is also possible to sense the rotary movement of the kingpin inserted into the fifth wheel coupling.

According to a third embodiment, the sensor can be a distance sensor for detecting the gap width between driver's cabin and front of trailer and it can recognize a bent position from a decrease in the gap width. When driving straight, the lengthwise axes of the towing vehicle and the trailer coincide. A distance sensor, arranged for example at the center, would measure a maximum distance. Once a curve begins, the inside corner of the trailer drifts in the direction of the lengthwise axis of the towing vehicle, so that the distance sensor measures a reduced distance between driver's cabin and front of trailer.

The above-described embodiment provides an especially direct measurement value, which reflects especially well the actual spatial conditions. Furthermore, the described use of a distance sensor can be utilized also to maintain a minimum distance between driver's cabin and towing vehicle in normal operation.

On occasion, it can happen with trailers that the distance from the kingpin to the front of the trailer is dimensioned very long and furthermore at times additional equipment is installed on the front of the trailer. In these cases, the distance sensor prevents the trailer from being drawn toward the driver's cabin during normal driving operation on high-speed expressways.

Advisedly, the control unit will calculate from the change in the measured value per unit of time an angle gradient or, in the case of the above-described third embodiment, a distance gradient.

Furthermore, it has proven to be advantageous for the control unit to be connected to the brake system of the towing vehicle and to receive a braking gradient from the braking system, or to generate such a value.

Advantageously, the slide is locked by the actuator upon exceeding a predetermined braking gradient and falling below a predetermined angle gradient.

BRIEF DESCRIPTION OF THE DRAWINGS

Advantageously, the locked position of the slide is released upon exceeding a predetermined braking gradient and exceeding a predetermined angle gradient.

For better comprehension, the invention will now be explained more closely by means of 6 figures. There are shown:

FIG. 1: a side view of a towing vehicle with a sliding device and attached trailer according to the prior art;

FIG. 2: a bottom view of the sliding device represented in FIG. 1, and

FIG. 3: a schematic side view of a first embodiment of the control system according to the invention;

FIG. 4: a schematic side view of a second embodiment of the control system according to the invention;

FIG. 5: a schematic side view of a third embodiment of the control system according to the invention;

FIG. 6: a schematic side view of the control system shown in FIG. 5.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows in a schematic side view an articulated vehicle with a towing vehicle 2 and a trailer 9 mechanically attached to it. The mechanical connection between the vehicles 2, 9 occurs via a fifth wheel coupling 3, which is arranged on a slide 5 and can move in the vehicle's lengthwise axis on two guide rails 4 spaced parallel to each other. The movement of the fifth wheel coupling 3 occurs during driving operation by its own specially provided motorized drive unit 7 in the form of a hydraulic cylinder and serves primarily to adjust the gap width W between the rear side of the driver's cabin 21 and the front of the trailer 22.

The sliding device 1 can be seen in an enlarged bottom view in FIG. 2. On the slide 5 there is an actuator 8, at right angles to the guide rails 4, with locking pieces 23 a, 23 b formed at the end, engaging in form-fitting manner with complementary seats (not shown) of the guide rails 4 and thereby locking the slide 5 to the guide rails 4. Before a movement of the slide 5 with the motorized drive unit 7, the locking pieces 23 a, 23 b are retracted via the actuator 8, which releases the mechanical locking.

A first embodiment of the invention is shown in FIG. 3. Here, the steering wheel 15 of the steering system 13 in the driver's cabin 21 is monitored by a sensor 12 and thereby recognizes a steering movement or change in the steering angle 14 (see FIG. 6). Alternatively, the sensor 12 could also detect the steering linkage 16 or parts of the steering gear 17. The sensor 12 is connected to an electronic control unit 6, which is furthermore connected to the motorized drive unit 7 and the actuator 8. Thanks to the control unit 6 and the sensor 12, an indirect inference is made as to the bent position of the trailer 9 relative to the towing vehicle 2.

FIG. 3 shows a rear position 11 a and a front position 11 b of the slide 5 and, thus, the front of the trailer 22, where for sake of clarity the front position 11 b is shown with dotted lines. The front position 11 b corresponds to the minimum gap width W₁ and the rear position 11 a to the maximum gap width W₂. The minimum gap width W₁ is dimensioned such that a full swinging of the front of the trailer 22 without a collision with the driver's cabin 21 is not possible.

Starting from the minimum gap width W₁ adjusted at high speed, in event of a steering maneuver this is recognized by the sensor 12 and provided to the control unit 6 as a measurement value. Depending on the angle gradient, that is, the steering wheel movement per unit of time, the actuator 8 is retracted upon exceeding a predetermined steering wheel gradient, thereby releasing the locking of the slide 5. After this, the motorized drive unit 7 forces the slide back to the rear position 11 a, in order to produce a maximum gap width W₂.

Additional system safety is achieved by additionally considering signals from the vehicle's brake system 10. In only a braking signal is present, the control unit 6 can leave the fixation of the slide 5 alone and additionally place the motorized drive unit 7 and the actuator 8 in a readiness mode.

An alternative detection of the bent position occurs in the control system according to FIG. 4. As the sensor 12 here, a rotary encoder 19 is used, installed in the contour of the fifth wheel coupling, in order to detect a swinging of the trailer 9 relative to the towing vehicle 2. The rotary encoder 19 is connected directly to the control unit 6, which in turn indirectly infers from the signal provided a bent position of the trailer 9 relative to the towing vehicle 2, corresponding to the relative angle 18 (see FIG. 6).

FIGS. 5 and 6 show another alternative embodiment of the invention, in which the sensor 12 is formed by a distance sensor 20 disposed on the rear wall of the driver's cabin 21. If a single distance sensor 20 is used, this should be placed, as is especially conspicuous in FIG. 6, centrally in the area of the lengthwise axis of the towing vehicle 2.

FIG. 6 shows the end of a negotiated curve, wherein the wheels 25 a, 25 b of the front axle 24 are deflected by a steering angle 14 with respect to straight driving movement. The inside corner of the front of the trailer 22 is situated in the area of the lengthwise axis of the towing vehicle 2 and stands directly opposite the distance sensor 20. In this position, the distance sensor 20 measures the least possible gap width W. In the subsequent straight travel and swinging back of the trailer 9, the distance sensor 20 shows the largest possible gap width W. For curves in the opposite direction, the gap width W detected by the distance sensor 20 decreases in the same way.

Thus, from the measured value of the distance sensor 20 the control unit 6 indirectly determines a bent position corresponding to the relative angle 18 of trailer 9 and towing vehicle 2.

List of reference numbers

-   1 sliding device -   2 towing vehicle -   3 fifth wheel coupling -   4 guide rail -   5 slide -   6 control unit -   7 motorized drive unit -   8 actuator -   9 trailer -   10 vehicle's brake system, brake system -   11 a rear position of the slide -   11 b front position of the slide -   12 sensor -   13 steering system -   14 steering angle -   15 steering wheel -   16 steering linkage -   17 steering gear -   18 relative angle -   19 rotary encoder -   20 distance sensor -   21 driver's cabin -   22 front of the trailer -   23 a, b locking piece, actuator -   24 front axle -   25 a, b wheel -   W towing vehicle/trailer gap width -   W₁ minimum gap width -   W₂ maximum gap width 

What is claimed is:
 1. A method for control of a sliding device for a fifth wheel coupling (3) arranged on a towing vehicle, comprising the steps of: the sliding device comprises a substructure having at least one guide rail oriented in a driving direction, a movable slide, which supports the fifth wheel coupling and engages on the guide rail, and a control unit, to which a motorized drive unit for moving the slide and an actuator for fixing the slide relative to the guide rail are connected, performing a measurement to detect a bent position of towing vehicle and trailer, processing a signal of the measurement into a control signal in the control unit, initiating a start-up of one or more of the motorized drive unit and the actuator therewith, and generating an angle or distance gradient from the signal of the measurement in the control unit, or this is relayed to the control unit.
 2. The method according to claim 1, wherein a braking gradient is generated from a braking signal of the vehicle's brake system in the control unit or a braking gradient is processed from the vehicle's brake system.
 3. The method according to claim 2, wherein the slide is locked by the actuator upon exceeding a predetermined braking gradient and falling below a predetermined angle gradient.
 4. The method according to claim 2, wherein a locked position of the slide is released by the actuator upon exceeding a predetermined braking gradient and exceeding a predetermined angle gradient.
 5. The method according to claim 4, wherein the slide is moved into a rear position by the drive unit after releasing the locked position.
 6. The method according to claim 1, wherein an actual speed of the towing vehicle is provided to the control unit and below a predetermined minimum speed the slide is held in a rear position on the guide rail or rails.
 7. A control system for control of a sliding device for a fifth wheel coupling arranged on a towing vehicle, comprising: the sliding device that comprises a substructure having at least one guide rail oriented in a driving direction, a movable slide, which supports the fifth wheel coupling and engages on the guide rail, and a control unit, to which a motorized drive unit for moving the slide and an actuator for fixing the slide relative to the guide rail are connected, wherein the control unit is connected to at least one sensor, which provides a measured value for detecting a bent position of towing vehicle and trailer, and it interacts with one or more of the drive unit and the actuator, wherein the control unit calculates an angle or distance gradient from a change in the measured value per unit of time.
 8. The control system according to claim 7, wherein the sensor is disposed in an area of the steering system and the sensor detects a steering wheel angle of the towing vehicle.
 9. The control system according to claim 7, wherein the sensor interacts with one or more of a steering wheel, a steering linkage, and a steering gear.
 10. The control system according to claim 7, wherein the sensor detects a relative angle between the towing vehicle and the trailer.
 11. The control system according to claim 10, wherein the sensor is a rotary encoder.
 12. The control system according to claim 7, wherein the sensor is a distance sensor for detecting a gap width (W) between a driver's cabin and a front of trailer and it can recognize a bent position from a decrease in the gap width (W).
 13. The control system according to claim 7, wherein the control unit is connected to a brake system of the towing vehicle and the control unit receives a braking gradient from the braking system, or generates such a value.
 14. The control system according to claim 13, wherein the slide is locked by the actuator upon exceeding a predetermined braking gradient and falling below a predetermined angle gradient.
 15. The control system according to claim 14, wherein the locked position of the slide is released upon exceeding a predetermined braking gradient and exceeding the predetermined angle gradient.
 16. The method according to claim 3, wherein a locked position of the slide is released by the actuator upon exceeding a predetermined braking gradient and exceeding a predetermined angle gradient, and wherein the slide is moved into a rear position by the drive unit after releasing the locked position.
 17. The method according to claim 16, wherein an actual speed of the towing vehicle is provided to the control unit and below a predetermined minimum speed the slide is held in a rear position on the guide rail or rails.
 18. The control system according to claim 8, wherein the sensor interacts with one or more of a steering wheel, a steering linkage, and a steering gear.
 19. The control system according to claim 16, wherein the control unit is connected to a brake system of the towing vehicle and the control unit receives a braking gradient from the braking system, or generates such a value.
 20. The control system according to claim 19, wherein the slide is locked by the actuator upon exceeding a predetermined braking gradient and falling below a predetermined angle gradient, and wherein the locked position of the slide is released upon exceeding a predetermined braking gradient and exceeding the predetermined angle gradient. 